


Hart of the Ocean

by CandyassGoth



Category: Kingsman (Movies), Kingsman: The Secret Service (2015)
Genre: Alternate Universe, BAMF Roxy, Babies, Breeding, Cloaca, Cloaca sex?, Dom Harry, First Meetings, First Time, Fish tank mermaids, Gentleman Harry Hart, Harry is also old okay, Hermaphrodites, How Do I Tag, It's just so cute, M/M, Mermaid Sex, Mermaids, Merman!Eggsy, Mpreg, Sub Eggsy, Tiny!Eggsy, Tiny!Hartwin!mermaid!babies, We sometimes play it down but animals wouldn't, Weird Biology, but he's still hella strong and gorgeous, i just needed babies okay, mermaid au, merman!harry, okay?, tiny!harry, yes good
Language: English
Status: Completed
Published: 2016-09-11
Updated: 2016-09-11
Packaged: 2018-08-14 10:30:31
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 6,749
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8010166
Author URL: https://archiveofourown.org/users/CandyassGoth/pseuds/CandyassGoth
Summary: <blockquote class="userstuff">
              <p>Eggsy, a common breed of domesticated merman, is purchased by a young woman from the store he grew up in. He tries to keep his expectations low so not to be disappointed, but he finds himself in a luxurious new home (complete with bubble blower), with a surprising tank-mate, and a new purpose. </p><p>It's all very sudden and posh.</p>
            </blockquote>





	Hart of the Ocean

**Author's Note:**

> Okay so, my knowledge of aquatic life and mermaids aren’t the best. But if tentacle porn can work, hey, we can do the mermaid stuff. 
> 
> Anyone seen the movie Splash? Used to love that movie as a kid. Rewatched it recently during Sunday lunch with the fam and this happened. Coz reasons. Also my mom said Eggsy could be called Leggsy the Mermaid, a tease on the fact that he has, well, no legs. She thought it was very funny. And then she said Harry could be Eric and Eggsy Ariel coz ‘isn’t that what you do online to these actors’. NAILED IT MOM. But fish tank pet mermaids are so much cuter I mean miniature Harry and Eggsy with pretty tails??? *sCREAMS*
> 
> So written in three hours off a whim. Don’t expect gold. Or, scratch that. You’ll see. And sorry for the terrible title pun.
> 
>  
> 
> _I apologise for errors_

** Hart of the Ocean **

 

It wasn’t that Eggsy wasn’t glad to finally leave the shop, he just wished his friends could’ve come with him. It was a fact of their lives that they’d be bought off at some point, but usually they were bought in pairs, trios or even groups. They even banded together when the nets came, clinging onto each other so when they were scooped up they were scooped together. But sometimes the human buying them wanted a selected catch, and that was how Eggsy went. He’d never see Ryan or Jamal again, but at least a new adventure awaited him. He had to stay positive.

The human that chose him was female, and thankfully an adult. Eggsy loved children, even human children, but even his patience had its limits when the little (huge, rather) creatures poked at the glass and dipped their hands in to catch them. He’d heard enough horror stories of human children yanking Mers out their tanks and obliviously suffocating them.

He’d never seen this human in the shop before, and he hoped he wasn’t the first and only Mer she had. He didn’t want to be alone forever, the thought made him tense. There was no hearing through the plastic bag they put in him, and seeing was just as difficult, so he just tried to remain calm and hope whatever the human was saying to him the entire time was words of comfort. 

They put his bag in a box, and off he went. No more staring through the four corners of his tank to see newcomers and interesting new breeds, and no more of the occasional fight with the local octopus that liked to slosh out of his tank and attack them. As dangerous as it was, octopus tasted as good to Mers as they did to octopus. It was just a matter of who got who first.

But no more fights, no more friends, no more wondering if he’d die of old age in the store, or if he’d get eaten by the octopus. He was onto a new life. He hoped there were snails in his new tank, those were delicious too.

After what felt like a lifetime, his box stopped moving. His new owner lifted him out and held the bag up to look at him, her face warped comically by the puckered plastic. He leaned over to get a better look and acknowledge her; humans loved it when they did that. 

She smiled, as expected, and starting talking, but it was to someone else in the room. Eggsy made out the enormous shape of another human, and he wondered if he’d been bought by a family anyway.

She carried him off, and he turned to see a large and thoroughly filled tank. His eyes widened. The tank wasn’t as big as the one he came from, but it was still decent and filled with so much green! Algae coated the glass healthily and there were ribbons of plants and fuzzy bushes placed all around, and in the centre was what looked like a little mountain with dark caverns. There were fish zipping around and a bubble blower (oh god _yes_ ), a heater (yesssss) and it looked completely empty. Okay, alone or not maybe he hit the jackpot. The most he’d been hoping for was a big rock to sleep behind.

The human held him above the water as she undid the band, being careful that he didn’t sway or jerk too much. The journey here was bumpy enough, and despite that he was hungry. Could he eat the fish? Was he allowed to? He was going to eat the fish.

Sound appeared for spilt second. The bag opened, and she poured him out into the tank. He let gravity take him with a soft _plop_ , and as soon as he stopped sinking he swum up towards the glass so he could turn and look around in awe.

It was even more beautiful from inside. It wasn’t just green, there were more colours than he’d ever seen, including from the batches of Bismuthiliidae Mer females that went through the store. The bedding was a soft-looking expanse of sand strewn with pebbles of all colours. He wanted immediately to dive in it and shuffle about, maybe see what treasures lay beneath. 

The place that must be the den was even better up close. It had so much detail it was good enough to fool him that he was in the wild. Not that he’d ever been there, but a Mer could dream. It was dark inside and he wondered how big it was and if there were fish hiding in there. He hadn’t seen any snails though. The fish were hiding now, grouping together in tiny shoals from his arrival. There were guppies and neon tetras, a stable diet for him. Guppies bred like you wouldn’t believe, and while tetras didn’t, they were apt at keeping a Mer fit to catch his meal. Snails though, bruv.

Eggsy was just about to go inspect the bubble blower when someone popped up behind him with no warning at all, only a light brush of the water. Eggsy jerked back and hissed, shaking the end of his tail in warning. The invader, another Mer, leaned away but otherwise didn’t retaliate, and took a long look at Eggsy.

“Hello.” He said eventually.

Eggsy lifted his fists and hunched his shoulders.

“All right, let’s do this.”

The Mer, much older than Eggsy was used to meeting, blinked and drifted another place back.

“Excuse me?”

“Fight. C’mon, then.”

The male raised a brow, still infuriatingly calm. “For what?”

Eggsy gestured around, eyeing out the other’s physique. He was long and lean, and noticeably old, he wouldn’t stand a chance against Eggsy’s build. He was a fancy Mer too, thick brown hair, his tail the brightest gold Eggsy had ever seen, glimmering and shimmering, with an extra flurry of paper thin fins down the sides of his tail that waved hypnotically. Mers like him weren’t built for fighting, they were notoriously known for being delicate. But so were Bismuthiliidae females and their bites were fatal.

“This place.” Eggsy said. 

If there was a group here then it would’ve been okay, he could join without question, but being dropped into a single Mer’s dominion called for a battle of dominance. Eggsy hadn’t gotten his hopes up just to let a posh merman tell him what’s what. He couldn’t see or smell any others, it was just them, and Eggsy could size up his opponent with confidence. He wasn’t one to brag, but he could win a fight.

“I’m not fighting you for this place.” 

“One of us is gonna have to.”

“Or we can just share.”

“Wot”

The male looked out the glass. “I’m fairly certain that’s what the humans intended.”

Eggsy glanced quickly, seeing the female approaching and beckoning with her hand. He looked around the tank. “Are you alone here?”

“I was. It’s just us. See? Plenty of room for us both.”

Eggsy lowered his arms and glanced dubiously at the mountainous fixture. “There’s only one den.”

The merman just blinked again. 

“Come see, Merlin, he’s already in there.” His owner said, staring at them through the glass. She looked much younger from in here, eyes big and bright as she watched them. 

A tall male human came up behind her and bent to have a look. Eggsy and Harry watched them back, and Eggsy got the feeling he wasn’t the only new Mer here.

“Roxy, are you sure you should have put them together right away? Westminster Mers are known to be a bit rough. Arthur will have our heads if anything happens to his Harry.”

“Only when threatened, and Harry’s not aggressive. He’s trained to handle difficult partners. Look, they’re okay.”

“This better work. Arthur is just waiting to run his mouth.”

“Oh please. He’ll be thanking us, and so will the Merology community.”

“All right then. Let’s leave them be and hope for the best.”

The female squealed and went around the side of the tank. Eggsy swam a few places away so he didn’t have to have his back to Harry while he watched his new owner flip a switch on the wall. A pale light illuminated from a bar at the top of the tank near the bubbles, and it intensified when suddenly the glass went black.

“What’s happening?” Eggsy swirled around and around, squinting against the pasty yellow light but he couldn’t see anything, she’d covered the tank with something.

“It’s all right, the light won’t hurt you.”

Eggsy wasn’t used to lights, save for the ones high up on the walls around the store. Never _in_ the tank with them. And he was starting to see why.

He faltered as a dizzy spell hit him, only for a moment, and then again a few seconds later. He shook his head and lifted his hands against the beam. He could almost feel it under his skin, heating his spine from his neck to the tip of his tail.

“It’s making me feel funny…”

“Come inside, it doesn’t reach there.”

Eggsy hesitated only a moment and followed _Harry_ into the den. It was almost pitch black, and then Harry pressed on a shell, and it came to life and lit up the den. The den was as big as Eggsy hoped, enough to swim about and find a private spot to sleep on at least three levels. He was about to ask where he could set up a bed when a hot gust of an unfamiliar need went through him, the light still shining behind closed eyes.

And suddenly he knew what was being _intended_.

“Are we…are we supposed to mate?” he asked, trying to keep his balance and shake off the effects of the light. He was glad the stranger wasn’t coming towards him, he felt disjointed from his limbs and wasn’t sure he could escape.

“We’re supposed to breed. My owner has been trying for a while to get me back in the business but it hasn’t been quite…it hasn’t been ending very well.”

Eggsy rested down near the entrance they came in through, pulling his tail up to make himself smaller, less parts to be attacked. Even the humans knew his kind of Mer were tough, but anyone could be prey when injured, even in the slightest. 

He pulled a face, both at the idea of suddenly mating with someone, and at the pieces of information. “How so? What do they mean trained?”

“I was a selected breeder in the day. I’m part of a very aristocratic breed, so I hear. I breed with all kinds of Mers, the offspring are quite grand. But the older I became the less healthy my offspring were. More died than I reared. A few mothers too.”

“But what can I do? Why’d she buy me?”

“Because you’re as common as they come.”

Eggsy pulled another face, cocking a dangerous brow, and Harry held his hands up, his stupid beautiful tail gleaming calmly beneath him.

“Your _breed_. Don’t misunderstand me, it’s not an insult but an observation. It’s far from an insult. That woman believes it’s the continuous mixing of Mers of my breed that are causing the problems. I think she’s right. Mers of my calibre and equal are for show and display, but it means we’re not as sturdy as the common Mer. If I were to mix with a hardy commoner perhaps it would yield better results.”

Eggsy shifted uncomfortably, shaking his head as a million fretful thoughts surfaced. “But…I’m not a breeder. Or for display. I’m…”

“You’re healthy and strong and not yet exclusive to one sex. You’re more adaptable than I ever was.”

Eggsy blinked. Then he scowled and pushed off the bedding.

“I didn’t go quietly just so I can be dumped here for you to breed till I die.” He growled and darted out, ignoring Harry’s calls about the light. 

Eggsy shut his eyes and swam around the back of the den. The light didn’t quite reach this side, only a sliver of a reflection, and he found corner to settle in before the effects of the light knocked him over. He panted into the fine sand, finding little comfort in the stones and plants now that they were no longer his.

He wasn’t reared as a breeder, he was just a common Mer meant to live with a shoal and entertain his owner by chasing fish and doing impressive swirls and flips in the water. Being a breeder was life-changing, body-changing, it would label him as one forever, and when Harry was done with him they could put him with the next merman to churn out young for the humans. He knew how it went, his mum was a breeder, and the last time he saw her she looked twice her age. He’d never see her again either, for good this time. Life wasn’t very long, and now he was brought here to produce rather than just live peacefully...

Eggsy waited with bated breath for the stranger to come find him, ready with his teeth and sluggish muscles. But he didn’t come, and Eggsy drifted off into an uneasy sleep.

 

The blackness and the funny light were gone every morning, and most of the day. But every afternoon their owner covered them up, and flipped on the ghastly light. Eggsy swam to his hiding place the moment the blackness dropped so the yellow couldn’t get him. He’d made a decent nest in his spot. After all, he was used to less. 

Aside from the annoying light and Harry’s awkward presence, Eggsy stubbornly made his home. He explored in the mornings, drifting section to section to find new things buried in the grass and sand, played with the bubble blower, and chased his meals enthusiastically whenever their owner peeked in, as intrigued as all humans were. On the third day she dropped in live worms, and Eggsy grabbed an armful before his gold-tailed companion realised they were there, and took them to his side of the tank. 

They didn’t talk much. Or, at all... Eggsy ignored him and his predictable greetings, and reluctantly snubbed the dead tetra offered to him once during a morning hunt. It wasn’t the Mer’s fault, but Eggsy needed someone to blame, and he wasn’t going to bite the hand that fed him—and that was the humans. So he chased his own food, coveted the worms and built a nest of leaves surrounded by blue stones—blue sort of like his tail. His tail was a common dull blue, not bright or flashy like a fancy Mer, but at least it wasn’t brown. He tried to ignore the pang of jealousy at his tank-mate’s beautiful tail. It was still lovely even at his age. His other owner, Arthur, must’ve really been looking after him. He probably got to eat snails everyday. But the worms as a treat weren’t bad, he supposed.

What was bad, though, was the light. It started getting to him. There was no way around it. 

Eggsy started getting sick.

It wasn’t serious, he didn’t think, but it didn’t help when he overheard the humans talking about what _could_ be wrong. It wasn’t a tumour or intestinal worms or a virus he might’ve come with; it was the bloody light punishing him for not doing what it commanded. He was constantly hot and jittery, trying to ignore Harry’s scent in the water despite every desire to sniff it out. But he persevered, resting his warm cheeks on cool rocks and floating near the surface, furthest from the heater to try and regulate his temperature. 

“Roxy, it’s not working. They don’t seem to be interested.” Merlin said as he watched Eggsy drift inanimately beneath the guppy shoal. Harry was somewhere on top of the den, winding plant stems and offshoots into a long thread. He rarely wandered around, he left that to Eggsy, and Eggsy grumbled at feeling grateful for the space. He could see the peace offering a mile away, aside from the tetra, and the intriguing gold amulet that happened to be left on the way to his nest.

Roxy stuck her face by the glass and bit her lip. Eggsy glared at her half-heartedly, too cranky to swim up and attack the light stick to get his point across.

“Maybe Harry is just past his prime?”

“Well, whatever it is, something’s gotta give. Arthur won’t leave him here for much longer if he’s not producing.”

“That’s cruel. Maybe he really is just past his time, it’s not just fault. Maybe Gary isn’t protandrous like they said? Or maybe I should just try another Mer, maybe a girl? One closer to his age? Ugh, it could be so many factors!”

“I think Harry’s just done. I’ve seen Arthur parade him during breeding spans. He knows how to seduce a mate. This isn’t it.”

Roxy worried her lip some more, and then they left. Eggsy sighed in relief that she didn’t turn on the light, but now he was worried about something else: Harry. 

Would they take him away, back to this Arthur? It looked like there was a lot of pressure on Harry to do this (Roxy stuck her face in every day, and seemed to leave disappointed), and yet, Harry hadn’t once put that pressure on him. It had been what, four or five days? He couldn’t even imagine how Harry must be feeling under the light, even with the den to hide in. The older and fancier you were the easier you got sick.

Eggsy debated with himself for a while before swimming up to Harry.

“Hey.”

Harry smiled at him, still twisting together his vines. “Hello.”

“Um...I’m Eggsy. Nice to meet you.” Eggsy greeted formally, offering his tail.

Harry looked pleasantly surprised, and tapped Eggsy’s tail with his. “Nice to meet you too.

“So...my mum was a breeder, and though she didn’t have posh ones like you she usually got charmed first. So why aren’t you charming me?”

“You made yourself quite clear.”

“Yeah, but,” Eggsy glanced off, out of the tank. Harry must have heard the humans talk. “What happens if we don’t breed?”

“I imagine you’ll be transferred to a communal tank.”

“And you?”

“Storage, I suppose.”

“By yourself?”

“I’m not as attractive as I used to be so I wouldn’t be set up for display anywhere of consequence. And it’s long been established that I do all right on my own.”

That was cruel indeed. Eggsy knew posh Mers often lived alone or in selective pairs, they had fussy opinions of the kind of mate to share their tank with, but living alone for what could be the rest of your life? That was sad. He’d gotten a fright when he thought Roxy had bought him to live alone, so he couldn’t imagine how Harry felt, living each day in the knowledge of his fate.

“...But you could still make attractive babies?” Eggsy asked, somewhat rhetorically, instead of saying _you’re not unattractive_. Harry was still plenty attractive for his age, Eggsy knew a dozen females back in the store that would’ve fought over him, stamina and strength be damned.

Eggsy scratched his neck uncomfortably, trying to sneak a scratch to his gills. They were a little puffy and irritable lately. “And I thought I was the one with the short stick...” He sighed and looked away to the colourful pebbles. “Look...”

“You don’t have to worry. I don’t have much to look forward to so even if I was put away or put down, I’m not too bothered. Frankly I just don’t think I could handle losing any more younglings. You’re too young to be put through that anyhow.”

“...But that’s the whole point. I’m young. You got the flash but I got the flesh. I reckon it would be okay. My mum was a Flavescensfere mermaid, but I took off my dad more, we’s just regular Westminsters... But maybe some of her flash will show up with yours and your owner would be really happy.”

“You’re not bland yourself, you know. You’re quite a sight. But you don’t have to risk it for me.”

Eggsy nodded, but he didn’t swim away like Harry seemed to think he might.

“My mum’s been through enough breeders that didn’t give her that choice. You’re giving it to me. Kinda only fair if I agree. I don’t mind, I just... I didn’t wanna be stuck here with a snobby Whatever-You-Are that thought he was perfect ‘cause he’s all shiny and posh. But I’m warning you if you’re tricking me I’mma punch you right in the dick.”

Harry laughed, a nice sound, and put down his threads and pushed off the den top.

“Let me get you food. May I?”

“Is that for courtship? Because I don’t need it.”

“It would be rude of me not to. Wait here.”

Well, Eggsy wasn’t going to steal his glory. He sat next to Harry’s threads and watched him chase down the fattest male guppy. They were never as big as the females (or as fast) but it wasn’t about the quantity, it was the quality. Even commons knew most mating rituals. Or breeding, rather, there _was_ a difference.

Harry returned with the most colourful one, limp but whole. Eggsy had been avoiding it on purpose, he liked watching it glimmer red, but he was too flattered to turn it down.

“Thanks.”

Harry puffed proudly as he ate, and then swam off, presumably to get his own. Eggsy munched it all down though he wasn’t very hungry, noticing the pretty patterns Harry was roping with the stems. Eggsy didn’t know what they were for, it was probably something fancy Mers did to entertain their humans. They would make good ties to make a snug nest with though.

He was so engrossed in his fish and Harry’s threading that he almost didn’t notice the shadow fall over the tank. He swallowed down the last of the red tail and found their owner looking at him.

“Hey, little guy. Good to see you eating. It’s a pity this didn’t work out... Merlin? Is the tank ready?”

“...What? No, wait—” Eggsy pushed off the den, but Roxy didn’t hear him, couldn’t understand his sounds in the first place, and looked over her shoulder.

“I can’t find the heater clutch!” Merlin called.

Eggsy darted away as Roxy did. 

“Harry? Harry!”

Harry bumped into him at a similar speed, and they spun to a stop, holding onto each other.

“Eggsy? What’s wrong?”

“They’re coming for us. They’re gonna take me away. We have to mate now!”

“But I haven’t lulled you yet, you’re not ready.”

“It doesn’t matter—!”

Eggsy didn’t get to argue his point. The next part happened so fast that he was gasping for breath and clawing at a white netting before he realised he was already being taken. 

Someone lifted him out the water, out of the tank, away from Harry, who, without him, would be labelled useless and taken away to be forgotten somewhere. Harry may be older than a preferred partner and—usually—above Eggsy’s rank, but Eggsy had always had a soft heart. He owed Harry nothing, but if living in a community taught him one thing, it was to help those around you. He couldn’t just turn his back on someone, not when he feared the same fate.

His owner’s voice appeared, louder than his sensitive ears could adapt to without the filter of water, and she cupped the netting holding him so he didn’t sag. 

This was his shot. Or rather it might be the only shot, and a terrible one at that.

Eggsy twisted and slapped his tail as hard as he could, smacking her hand and propelling right out of the net. 

He hadn’t expected to make it back in the tank, but he landed besides it on the counter with a loud _smack_ , gasping weakly for the little air his lungs could take in outside of water.

He heard a scream and vaguely saw his owner doing a funny dance, he wasn’t too sure with his eyes drying out, and then he was grabbed again, and dropped back into the tank before he could panic over being held in a bare human hand.

Eggsy took a large breath as he let himself sink, blinking repeatedly as a two hazy forms came zipping towards him, his head throbbing a little.

Outside the tank the Merlin reappeared. “What happened? Did he bite?”

“He jumped out of the net! They told me he was strong but Merlin _he jumped right out_! I threw him back in, I panicked!”

Merlin bent to look at the Mers. “Well, not for nothing it seems. Look.”

Harry sped up and grabbed Eggsy, holding him up around the waist from the back so Eggsy didn’t have to exert himself.

“Foolish boy! You could’ve hit the floor!”

“I-I should’ve just let you when we—when we first met. It’s not f-fair on you!”

Roxy and Merlin shared looks as Harry embraced Gary, holding him up while the younger caught his breath. It was the most contact they’d had since being put together, or at least the most Roxy had seen. She’d checked every day, but it hadn’t seemed like they’d even greeted.

“...Is this good? Did we miss something?”

In the tank Eggsy panted, and turned to face Harry. 

“Lull me. Start now. They need to see.”

Harry looked dubious, brushing his fingers over Eggsy’s irritated gills.

“Are you sure?”

“Yes. As long as you swear to help me! I can’t raise babies on my own. I’ve seen in happen and it ain’t fair either!”

“I swear,” Harry breathed, and drew Eggsy in by the neck to rub his nose against his face. 

“Oh my God!” Roxy shouted, smacking Merlin repeatedly on the arm. “It’s happening! It’s happening?!”

“ _I can see._ ”

Eggsy let Harry mark his face. It was an offering of trust on both their sides, and neither of them bit the other. He tried to ignore the female’s screeching outside, worrying that she was mistaking their union for a fight, and then Harry backed away.

“Wait here.” He said, and swam up to the top, and looked pointedly towards the humans as he patted the enemy light.

“Holy shit.” was all Roxy said before fumbling to turn it on.

“Maybe we should leave them?” Merlin said, pulling on her arm.

“But it would be nice to at least make sure...?”

“I’m your witness. Arthur can’t demand Harry now back until a month is up. We should know in two weeks away.”

“Okay, _okay_...” Their owner gave another high pitched cry and Eggsy watched her skip away through squinted eyes. They didn’t cover them this time, and it greatly lessened the effect of the light. 

Still, it sunk right into his skin and with a pout of betrayal he watched Harry come down, tail bright in the light.

“I don’t like the light. They don’t have them where I’m from. Why isn’t it affecting you?” Eggsy asked.

“I’ve long gained a resistance. I’m sorry, but it’s to help lull you. It’ll stop worrying you the moment after we breed.”

Eggsy groaned and pressed his face into Harry’s neck. His instincts fluttered pleasantly when Harry nuzzled him, trusting him not to bite at his vulnerable gills. In turn he let Harry caress his neck, soothing the itchiness.

He _could_ feel the light trying to lull him, making his head light and eyes heavy, but his body buzz with the gnawing, foreign need to procreate. 

Though kept in groups, Mers didn’t breed willy-nilly, perhaps an inborn instinct preventing over population, which could become catastrophic in small spaces like man-made tanks. Breeders are selected by humans and conformed into the role and given their own space when breeding, so it was safe for Eggsy to say he’d never felt the desire that was currently searing through his gut. 

Eggsy had wondered, like any Mer, if he’d ever mate, but he’d never thought he’d be honoured to a mating dance. It was used for breeding too, to seduce a stranger, but Eggsy never thought he’d received one. He’d never thought he’d be picked to mate females, so he hadn’t thought he’d _give_ one either, but as Harry held him by the waist and swirled them around, tail wriggling in deft little movements that presented both eagerness and worthiness, Eggsy couldn’t help feeling giddily excited as he watched his own breeding unfold.

Harry led. He clearly knew what he was doing, and seemed quite capable of guiding Eggsy’s along with him. He turned them this way and that, a full flip and then a twirl, disrupting the calm current and hypnotising Eggsy’s twitching body until it learnt the rhythm and forgot about the funny throbbing of his cloaca. 

Then Harry took him around the waist and pulled him down into the lush of the mossy bedding. He pressed Eggsy down and held him there, exhibiting quite a feat of strength manhandling Eggsy’s considerable dead weight against the water. Eggsy gurgled at the display and arched, winding his tail around Harry’s in an unconscious but progressive action.

“You’re stronger than you act.” He said, panting.

“It’s just the breeding frenzy,” Harry whispered into his ear, making Eggsy shudder, voice low and secretive. “How am I enticing to you if I’m not at least marginally fit?”

“I already said you don’t have to court me.” Eggsy brushed his hands up Harry’s chest and into his hair, admiring the softness yet the durability as he pulled. Harry’s tail tightened around him in response and pressed them flush together, and Eggsy gasped at the feeling of something pressing between them, something that wasn’t his.

“I heard _you_ , but instincts can be surprisingly picky, even with common Mers.”

Eggsy nodded in agreement. His skin prickled and he felt his cloaca warm pleasantly as Harry pressed against him, the fins down his tail waving hypnotically as he wound his beautiful golden tail tighter and tighter around Eggsy’s. He was truly a sight; Eggsy could only imagine what their offspring would look like. He wouldn’t have to wait too long, and he was already anxious.

Harry’s chest was harder than it looked, and so were his hands. He slid his arms under Eggsy’s and strapped them up his back and held his shoulders, making sure Eggsy had no place to move, entirely trapped. It should worry Eggsy, but this wasn’t the octopus, this was a gentle merman who cared enough to make calming sounds into his mouth as he squirmed against Eggsy, aiming and catching his target with a control thrust.

Eggsy threw his head back as Harry entered him. It was the most he could do as he jolted. Harry tightened his hands over Eggsy’s shoulders and his tail was locked, a thick sinew of muscle that was deceptively stronger than Harry pretended. The knowledge excited Eggsy’s bubbling instincts and his passage opened a little more, granting Harry blessing to breed with him, being the strong, gorgeous merman that he was. Hermaphroditism was common with common Mers, at least until conformed into breeding roles, and Eggsy felt his body tingle as it shifted towards the appointed role. 

“You’re so beautiful.” Harry whispered to him, and Eggsy found he believed it. He believed every word Harry breathed into his ear, whether humbly true or ridiculously false, and pressed up into each of Harry’s careful, well timed thrusts. Harry smelt divine and Eggsy wanted to sink into his skin and fuse, and Harry whetted the desire admirably by moulding them together against the sand.

His thrusts were deep and firm, stretching Eggsy’s inexperienced little passage with a wriggling appendage. It was causing part of the scent Eggsy picked up, slipping into his slit with a kind of slickness thicker than water. It was longer than it was thick and each time Harry’s hips met Eggsy’s it assaulted a new place inside Eggsy, awakening a potential in his body with each pleasurable thrust.

It felt better than Eggsy had hoped, his tunnel searing and throbbing as it held snuggling to Harry’s probing phallus, every slap tight of their body’s smacking Eggsy higher and higher towards a climax. 

Instinctively, only on the cusp, Eggsy knew once he climaxed his body would change forever. He’d hold for a couple of day whatever seed Harry put in him, and when the strongest took root, he’d become pregnant, and bear Harry’s live offspring in a few weeks. He’d lost all his family and friends, but gaining some wouldn’t be bad at all.

Harry climaxed first, Eggsy’s instincts agreed to it, for it set off his own. He moaned as Harry buried him into the sand, tucked safely under his body as he pressed their tails together and deposited his seed. He held still despite Eggsy’s wriggling for more thrusts, shooting rope after rope into the pouch that was already in a slow transition into a womb. 

The filling set off Eggsy’s high and he came with a loud shriek, squeezing Harry’s arms as his body seized up. The pleasure mounted painfully and just when it became too much Harry swiftly pulled out, allowing Eggsy’s pouch to close, saving his own appendage in the first place.

Eggsy writhed as waves of pleasure ebbed from his tail fins to his throat, bringing alive every inch of flesh he had. He whimpered and whined as the feelings overwhelmed him, so much more powerful than the triumphant feeling of having torn off an octopus leg and eating it as a prize. While Harry had pulled out he didn’t separate, and coiled himself around Eggsy in a gentle, still embrace. It was all consuming and Eggsy cooed, protected and hidden from sight, even though there was no one else around to hurt him, as his body recovered. 

He blinked up at the yellow light, and, as he learnt from the humans, gave it the finger.

 

Two weeks later, Roxy screamed the house down. She skipped and danced around the tank and Merlin as if doing some sort of human mating ritual, clapping her hands and talking excitedly. 

Eggsy blushed and pouted, arms crossed as he drifted besides Harry who came to collect the worms Roxy dropped in. Usually Harry came alone, Eggsy had been too shy to come out when the humans were around, but he found her approval strangely satisfying. 

His belly had a nice swell, he could’ve shown them at least four days ago, but between self-preservation instincts and first-time shyness Eggsy hid away until the last possible moment. Harry didn’t seem to mind, he wore a smile that said he’d seen this before, and altruistically fetched all the food, and kept an eye out for the humans when Eggsy climbed out of the den for a swim.

Roxy babbled on about a dozen things, how the babies would look, how ‘it’ had worked, she’d have to call a vet, how many babies it’d be, how Arthur could suck it—Eggsy was just glad she was glad. And, he was glad Harry was glad. It all made him glad too and more excited with each passing day. 

At night in the den, in the large and frustratingly perfect nest Harry had already constructed, they would lie together, and Harry would rub his belly, and then preen him from head to tail. It was close to worship and not something a common Mer’s instincts even thought to crave, but they enjoyed it all the same. Eggsy basked, feeling appreciated, and hoped this was how his mum felt at least most of the time.

 

“Well, this is quite the surprise. I’d almost given up on him.”

Roxy smiled smugly, watching the Mers with a shine in her eyes as Arthur had a look at the outcome four weeks later. “Dr. Valentine has assured us that they’re all healthy and guaranteed to be perfectly fine. Think three of them are going to take after Harry in particular. It’s a success.”

“Yes, I suppose there is use for these gutter fish. Just like the lower class, good only for breeding.”

Eggsy hunched, hiding away his smallest, and commonest, child in his arms. Harry put a hand on his shoulder, but Eggsy didn’t relent in his glaring until Arthur said something too soft to hear, and walked away. Roxy smiled at them, and stayed where she was. She could barely leave them alone.

Only when the old human was gone did Eggsy relax, and let Harry take his gaze.

“Don’t listen to him.” Harry said. “I’ve only ever been used to breed. _I_ needed _you_ to have this. Look at them. They’re perfect, because of you. There’s a reason aristocrats developed weak chins. I’m just the flash.”

They _were_ perfect. Eggsy puffed up, he couldn’t help feeling proud, and glanced around at the four babies swimming around their tails. Three were certainly of Harry’s breed, glittering golden tails, and to match, golden hair. They’d gotten that from Eggsy’s mum, and Harry was apparently just as awestruck. He’d never had offspring with yellow hair, and even after all his years, he was genuinely surprised and amazed. Two were female, one was male.

The other two took after Eggsy. Blue tails and auburn brown hair. They weren’t very flashy, and the runt was quite small, but the other was the largest of them all, and both were male. Or, they would be until a day came when chosen to fulfil a secondary role, as he did. 

“Here,” Harry said, taking the runt from him and urging him down to swim with his siblings. They were throwing up the sand and seeing who could lift the heaviest stones, blissfully unaware of what a surprised miracle they were.

Eggsy pulled his lips, he was over protective of his smallest despite common sense acknowledging that were was no danger around, but he gave Harry his attention, and made a pleased clicking sound in the back of his throat when Harry took him by the waist and swirled him around. They spun up in a circle and then Harry dipped them down, leading so Eggsy could close his eyes and simply drift along, swishing his tail a little at every turn.

Doing a double take, Roxy waved her arm until Merlin thought it would wind out. “Merlin! Merlin, they’re doing the dance.”

Merlin leaned over, careful not to cast a shadow and disrupt the pair. 

“Gary can’t breed this soon, he’s just given birth?”

Roxy blinked. “I don’t think its breeding. I think...I think it’s _mating_. Mates.”

“...I’m not witnessing this against Arthur.”

“Oh, this is perfect! I have to call Valentine! He’ll validate them as a pair and I can keep Harry!”

“You had your eye on him the whole time didn’t you?”

“You didn’t think I was going to just stand around and watch Arthur abuse this poor merman, did you? He should be enjoying his twilight years. Now I can see to that.”

“You sneaky girl.”

Eggsy turned his head back, upside down as he looked at the humans.

“Did you hear that? They think we’re mating? They’re gonna keep us together.” He said, surprised and excited and unsure of what that meant all at once. Harry did the dance with him a lot, he hadn’t thought much on it, he just knew it calmed him and Harry seemed to enjoy doing it. It was the first time they did it in front of the humans though. Eggsy hadn’t thought of it as mating and Harry hadn’t suggested. It didn’t make Eggsy anxious though, the thought felt right, especially with the little bodies making a ruckus below them

Harry drew them to a stop and hugged him, nuzzling his face and petting long strokes down his back, as the younglings swam up a bit to pull and fiddle with their tails. Eggsy had to shoo them from Harry’s more often than not, those side fins _were_ as delicate as they looked.

“ _She’s_ going to, and I don’t think we’ll have to worry about breeding again. Unless you want to.”

Eggsy grinned, and kissed Harry on the cheek. 

“Well, I can’t say I wanna punch you in the dick anymore.”

 

**XxXxXxXxXxXxXxXx**

**Author's Note:**

> Seriously you go for pointless smut/fluff, and world building just slithers in there. wtf man


End file.
